Waiting for lock on registry/.registry.lock when using macports

When using macports to install packages, you might see

Waiting for lock on /opt/local/var/macports/registry/.registry.lock

This is due to the macports did not end properly last time.

Try to run this code

sudo rm /opt/local/var/macports/registry/.registry.lock

would solve this problem.

I recommend using Homebrew instead of Macports on modern Macs. Check this article to learn how to install it: Apps I Install on My Mac